Sensitivity of Swedish interactive threshold algorithm compared with standard full threshold algorithm in Humphrey visual field testing

Abstract

Objective: To compare the sensitivity of Swedish interactive threshold algorithm (SITA) strategies with the standard full threshold algorithm in the Humphrey Field Analyzer.

Design: Observational case series.

Participants: Forty-eight glaucoma patients who were experienced in automated perimetry.

Testing: Central field testing was performed with the 30-2 program using standard full threshold (SFT), SITA standard (SS), and SITA fast (SF) strategies. All three tests were carried out on each of four different days in a span of 4 weeks.

Main outcome measures: Sensitivity, repeatability, time saved, and the extent of defect in the SITA strategies were compared with those of the SFT.

Results: The sensitivity of SS and SF were 95.12% and 92.68%, respectively. The time saved in SS and SF was 53.12+/-9.51% and 70.69+/-8.81%, respectively. The repeatability as assessed by intraclass correlation showed excellent repeatability for the SFT and SS strategies and excellent to poor repeatability with the SF strategy. With increasing mean deviation, the defects (significant at P<0.5%) in the pattern deviation plots tended to be more in the SITA strategies as compared with SFT.

Conclusions: Swedish interactive threshold algorithm strategies have good sensitivity and are significantly faster as compared with the standard threshold algorithm. The repeatability of the SFT and SS strategies are excellent, whereas that of the SF strategy is variable.